Rotational Equilibrium and Rotational Dynamics

Question 1

• ____ cause accelerations
• ____ cause angular accelerations

Answer 1

Force

Torque

Question 2

is the tendency of a force to rotate an
object about some axis

Answer 2

Torque

Question 3

When two or more torques are acting on an
object, the torques are added
* As vectors
➢ If the net torque is zero, the object’s rate of
rotation doesn’t change

Answer 3

Multiple Torques

Question 4

The applied force is not always perpendicular to
the position vector
➢ The component of the force perpendicular to the
object will cause it to rotate
➢ When the force is parallel to the position vector,
no rotation occurs

➢ When the force is at some angle, the
perpendicular component causes the rotation

Answer 4

General Definition of Torque

Question 5

d, is the perpendicular distance
from the axis of rotation to a line drawn along
the direction of the force

Answer 5

Lever Arm

Question 5

The ____ is the sum of all the torques produced
by all the forces

Answer 5

Net Torque

Question 6

When a rigid object is subject to a net torque (Στ ≠
0), it undergoes an ____

Answer 6

Angular Acceleration

Question 7

The angular acceleration is inversely
proportional to the analogy of the mass in a
rotating system

Answer 7

Moment of Inertia

Question 8

• An object rotating about some axis with an angular
  speed, ω, has ____ energy KEr = 1⁄2Iω2

Answer 8

Rotational Kinetic Energy

Question 8

• Similarly to the relationship between force and
  momentum in a linear system, we can show the
  relationship between torque and ____

Answer 8

angular momentum